function showPic(whichpic) {
	if(!document.getElementById("placeholder")) return false;
	var source = whichpic.getAttribute("href");
	var placeholder = document.getElementById("placeholder");
	placeholder.setAttribute("src", source);
	if(document.getElementById("description")) {
		var text = whichpic.getAttribute("title");
		var description = document.getElementById("description");
		description.firstChild.nodeValue = text;
	}
	return true;
}

function prepareGallery() {
	if(!document.getElementById) return false;
	if(!document.getElementsByTagName) return false;
	if(!document.getElementById("imagegallery")) return false;
	var gallery = document.getElementById("imagegallery");
	var link = gallery.getElementsByTagName("a");
	for(var i = 0; i < link.length; i++) {
		link[i].onclick = function() {
			return showPic(this) ? false : true;
		}
	}
}

function addLoadEvent(func) { //load function
	var oldonload = window.onload;
	if(typeof window.onload != 'function') {
		window.onload = func;
	} else {
		window.onload = function() {
			oldonload();
			func();
		}
	}
}

function insertAfter(newElement, targetElement) { //insert element after some element
	var parent = targetElement.parentNode;
	if(parent.lastChild == targetElement) {
		parent.appendChild(newElement);
	} else {
		parent.insertBefore(newElement, targetElement.nextSibling);
	}
}

function preparePlaceholder() {
	var placeholder = document.createElement("img");
	placeholder.setAttribute("id", "placeholder");
	placeholder.setAttribute("src", "img/imageConnect.GIF");
	placeholder.setAttribute("alt", "my image gallery");
	var description = document.createElement("p");
	description.setAttribute("id", "description");
	var desctext = document.createTextNode("Choose an image");
	description.appendChild(desctext);
	var gallery = document.getElementById("imagegallery");
	insertAfter(placeholder, gallery);
	insertAfter(description, placeholder);
}

addLoadEvent(prepareGallery);
addLoadEvent(preparePlaceholder);